Indirect Bonding
Several techniques for indirect bonding are available. Most are based on the procedures described by Silverman and Cohen.
In these techniques brackets are attached to the teeth on the patient’s models, transfer to the mouth with some sort of tray into which brackets become incorporated, and then bonded simultaneously.
Advantages
1. More accurate positioning of brackets.
2. Reduction in clinical chair time.
Disadvantages
1. Removal of excess adhesive is more difficult and time consuming.
2. Risk for adhesive deficiencies under the brackets is greater.
3. Failure rates are slightly higher.
Several indirect bonding techniques have proved reliable in clinical practice. They differ in the way –
A. Brackets are attached temporarily to model
1. Caramel Candy
2. Laboratory adhesive
3. Bonding resin
4. Sticky wax
Several techniques for indirect bonding are available. Most are based on the procedures described by Silverman and Cohen.
In these techniques brackets are attached to the teeth on the patient’s models, transfer to the mouth with some sort of tray into which brackets become incorporated, and then bonded simultaneously.
Advantages
1. More accurate positioning of brackets.
2. Reduction in clinical chair time.
Disadvantages
1. Removal of excess adhesive is more difficult and time consuming.
2. Risk for adhesive deficiencies under the brackets is greater.
3. Failure rates are slightly higher.
Several indirect bonding techniques have proved reliable in clinical practice. They differ in the way –
A. Brackets are attached temporarily to model
1. Caramel Candy
2. Laboratory adhesive
3. Bonding resin
4. Sticky wax
B. Type of transfer tray
1. Silicon
2. Vacuum formed
3. Acrylic with transfer arm
The two most popular techniques are the Silicon impression material and the double sealant.
Indirect Bonding with Silicon Transfer Trays
1. An impression is taken and a stone model is poured. The model must be dried. It may be marked for long axis and incisal or occlusal height on each tooth.
2. Brackets are selected for each tooth.
3. A small portion of water – soluble adhesive is applied on each base or tooth.
4. The brackets are positioned on a model and checked for all measurements and alignments.
5. For silicon tray fabrication, the material is mixed and the putty is pressed onto the cemented brackets. The tray is formed allowing sufficient thickness for strength.
6. After the silicon putty has set, the model and the tray is immersed in hot water to release the brackets from the stone. Any remaining adhesive is removed under running water.
7. The silicon tray is trimmed and the midline is marked.
8. The patient’s teeth are prepared as for a direct application.
9. The adhesive is mixed, loaded in a syringe and a sufficient portion is applied to the bonding bases.
10. The tray is seated on the prepared arch and held with firm and steady pressure for three minutes.
11. The tray is removed after ten minutes. The tray may be cut longitudinally or transversely to reduce the risk of bracket debonding when it is peeled off.
12. The bonding is completed by careful removal of excessive flash. Oval or tapered TC bur is used to clean the area properly around each bracket. The area around the bracket pad is inspected for adhesive voids and filled in with a small mix of adhesive if needed.
Disadvantages
1. Brackets are not visible under the tray.
2. Light cured resins cannot be used.
Indirect Bonding with a double-sealant technique
In this technique of bonding, adhesive pastes, rather than a temporary adhesive, are used to attach the brackets to the patient’s stone model.
1. Small portions of catalyst and universal adhesive pastes are dispensed side by side on a mixing pad.
2. On a per tooth basis, enough adhesive for one attachment is mixed and applied to the back of the bonding base.
3. The bracket is placed on the model, and the excess adhesive is removed from the periphery of the base. This step is repeated until all brackets are bonded to the stone model.
4. After at least 10 minutes, a placement tray is vacuum-formed for each arch.
5. Models with trays attached are placed in water until thoroughly saturated.
6. The trays are then separated and trimmed so that gingival edge of each tray is within 2mm of the brackets.
7. Midline is marked with indelible ink.
8. The embedded bonding bases are lightly abraded with a mounted stone point, after which the placement tray is ready for clinical use.
9. The clinical procedure is begun with the customary prophylaxis, isolation and etching of the patient’s teeth.
10. The lingual sides of the bonding bases are painted with catalyst sealant resin (Part B).
11. The dry-etched teeth are painted with the universal sealant resin (Part B).
12. The tray is then inserted into the patient’s mouth, seated and held in place for at least 3 minutes. It is removed by peeling from the lingual towards the buccal.
13. Excess flash of sealant is carefully removed from the gingival and contact areas of the teeth.
Advantage of this technique
Clean up is simple because little flash is present and consists of unfilled sealant only.
Newer Techniques
1. Use of Surebonder dual temperature hot glue – Larry White (1999) introduced a new matrix or tray material which is more rigid and still has enough elasticity and flexibility to permit easy removal after polymerization.
Previous trays used failed to get all the brackets to adhere to the teeth. Usually 2-3 brackets would come out with the matrix when it was removed.
Larry White used Surebonder dual temperature hot glue gun. The gun is simply a heating element that liquifies the solid glue stick and then places glue where it is needed. The gun has a dual temperature control. The low temperature is suitable for indirect bonding.
Procedure
1. After marking the teeth on the cast, two thin coats of separating liquid are applied to all tooth surfaces.
2. The brackets are sprayed with silicon spray to lubricate their surfaces and make it easier to remove the matrix.
3. The glue gun is used to form a molten matrix over the entire lingual and occlusal surfaces. The brackets are covered only partially with care taken not to get hot glue in the bracket slot.
4. Before the glue sets, the technician should pat the molten glue into a close conformation.
5. After the glue cools and hardens, the matrix and the brackets are submerged in water for about 30 minutes to dissolved the tacky glue and separate bracket and matrix from the cast.
J.C. ENDIRECT technique by Jay Collins (2000)
In this technique a new ultra viscous water soluble and tenacious bonding adhesive J.C. ENDIRECT is used.
Procedure
1. The casts are trimmed and the labial and the buccal surfaces to be bracketed are marked with a fluorescent yellow marking pen. This eliminates the need for separating media, while providing visual aid to improve accuracy of bracket placement.
2. The horizontal and vertical lines are marked.
3. 5cm bead of J.C. ENDIRECT adhesive is placed on mixing pad and each bracket base is placed against it until most of the bracket base is covered with adhesive. The bracket is then placed on the working cast.
4. A soft plastic mouth guard is vacuum formed.
5. The transfer tray is then trimmed into sections and returned to the cast.
6. A rigid clear plastic sheet is then vacuum formed over bracketed soft transfer tray. Therefore a dual tray system is formed.
A precise bracket location is reproduced and J.C. ENDIRECT has necessary viscosity to prevent bracket drift.
New products for Light Cured Indirect Bonding – Larry White (2001)
1. Quick Cure – A composite adhesive with a photoinitiator catalyst that is highly sensitive to a broader range of blue light.
2. Power Slot – It is the tip of a light curing unit that concentrates the beam of visible light and thus reduces polymerization time.
When Quick Cure and Power Slot are used, the composite will set with only 3 seconds of curing per tooth.
3. Prompt-L-Pop – It is all in one self etching adhesive supplied in a disposable single application unit. The etchant and sealant are combined and no rinsing is required after application.
1. Silicon
2. Vacuum formed
3. Acrylic with transfer arm
The two most popular techniques are the Silicon impression material and the double sealant.
Indirect Bonding with Silicon Transfer Trays
1. An impression is taken and a stone model is poured. The model must be dried. It may be marked for long axis and incisal or occlusal height on each tooth.
2. Brackets are selected for each tooth.
3. A small portion of water – soluble adhesive is applied on each base or tooth.
4. The brackets are positioned on a model and checked for all measurements and alignments.
5. For silicon tray fabrication, the material is mixed and the putty is pressed onto the cemented brackets. The tray is formed allowing sufficient thickness for strength.
6. After the silicon putty has set, the model and the tray is immersed in hot water to release the brackets from the stone. Any remaining adhesive is removed under running water.
7. The silicon tray is trimmed and the midline is marked.
8. The patient’s teeth are prepared as for a direct application.
9. The adhesive is mixed, loaded in a syringe and a sufficient portion is applied to the bonding bases.
10. The tray is seated on the prepared arch and held with firm and steady pressure for three minutes.
11. The tray is removed after ten minutes. The tray may be cut longitudinally or transversely to reduce the risk of bracket debonding when it is peeled off.
12. The bonding is completed by careful removal of excessive flash. Oval or tapered TC bur is used to clean the area properly around each bracket. The area around the bracket pad is inspected for adhesive voids and filled in with a small mix of adhesive if needed.
Disadvantages
1. Brackets are not visible under the tray.
2. Light cured resins cannot be used.
Indirect Bonding with a double-sealant technique
In this technique of bonding, adhesive pastes, rather than a temporary adhesive, are used to attach the brackets to the patient’s stone model.
1. Small portions of catalyst and universal adhesive pastes are dispensed side by side on a mixing pad.
2. On a per tooth basis, enough adhesive for one attachment is mixed and applied to the back of the bonding base.
3. The bracket is placed on the model, and the excess adhesive is removed from the periphery of the base. This step is repeated until all brackets are bonded to the stone model.
4. After at least 10 minutes, a placement tray is vacuum-formed for each arch.
5. Models with trays attached are placed in water until thoroughly saturated.
6. The trays are then separated and trimmed so that gingival edge of each tray is within 2mm of the brackets.
7. Midline is marked with indelible ink.
8. The embedded bonding bases are lightly abraded with a mounted stone point, after which the placement tray is ready for clinical use.
9. The clinical procedure is begun with the customary prophylaxis, isolation and etching of the patient’s teeth.
10. The lingual sides of the bonding bases are painted with catalyst sealant resin (Part B).
11. The dry-etched teeth are painted with the universal sealant resin (Part B).
12. The tray is then inserted into the patient’s mouth, seated and held in place for at least 3 minutes. It is removed by peeling from the lingual towards the buccal.
13. Excess flash of sealant is carefully removed from the gingival and contact areas of the teeth.
Advantage of this technique
Clean up is simple because little flash is present and consists of unfilled sealant only.
Newer Techniques
1. Use of Surebonder dual temperature hot glue – Larry White (1999) introduced a new matrix or tray material which is more rigid and still has enough elasticity and flexibility to permit easy removal after polymerization.
Previous trays used failed to get all the brackets to adhere to the teeth. Usually 2-3 brackets would come out with the matrix when it was removed.
Larry White used Surebonder dual temperature hot glue gun. The gun is simply a heating element that liquifies the solid glue stick and then places glue where it is needed. The gun has a dual temperature control. The low temperature is suitable for indirect bonding.
Procedure
1. After marking the teeth on the cast, two thin coats of separating liquid are applied to all tooth surfaces.
2. The brackets are sprayed with silicon spray to lubricate their surfaces and make it easier to remove the matrix.
3. The glue gun is used to form a molten matrix over the entire lingual and occlusal surfaces. The brackets are covered only partially with care taken not to get hot glue in the bracket slot.
4. Before the glue sets, the technician should pat the molten glue into a close conformation.
5. After the glue cools and hardens, the matrix and the brackets are submerged in water for about 30 minutes to dissolved the tacky glue and separate bracket and matrix from the cast.
J.C. ENDIRECT technique by Jay Collins (2000)
In this technique a new ultra viscous water soluble and tenacious bonding adhesive J.C. ENDIRECT is used.
Procedure
1. The casts are trimmed and the labial and the buccal surfaces to be bracketed are marked with a fluorescent yellow marking pen. This eliminates the need for separating media, while providing visual aid to improve accuracy of bracket placement.
2. The horizontal and vertical lines are marked.
3. 5cm bead of J.C. ENDIRECT adhesive is placed on mixing pad and each bracket base is placed against it until most of the bracket base is covered with adhesive. The bracket is then placed on the working cast.
4. A soft plastic mouth guard is vacuum formed.
5. The transfer tray is then trimmed into sections and returned to the cast.
6. A rigid clear plastic sheet is then vacuum formed over bracketed soft transfer tray. Therefore a dual tray system is formed.
A precise bracket location is reproduced and J.C. ENDIRECT has necessary viscosity to prevent bracket drift.
New products for Light Cured Indirect Bonding – Larry White (2001)
1. Quick Cure – A composite adhesive with a photoinitiator catalyst that is highly sensitive to a broader range of blue light.
2. Power Slot – It is the tip of a light curing unit that concentrates the beam of visible light and thus reduces polymerization time.
When Quick Cure and Power Slot are used, the composite will set with only 3 seconds of curing per tooth.
3. Prompt-L-Pop – It is all in one self etching adhesive supplied in a disposable single application unit. The etchant and sealant are combined and no rinsing is required after application.
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